The most appropriate diagnostic test to evaluate this patient's dysphagia is videofluoroscopy. Dysphagia is classified as either oropharyngeal dysphagia (also called transfer dysphagia) or esophageal dysphagia. Each of the two kinds of dysphagia has distinct epidemiology, pathophysiology, and management implications. Oropharyngeal dysphagia usually occurs immediately with deglutition. Causes of oropharyngeal dysphagia may be either neuromuscular or anatomic. Patients may have associated symptoms that provide clues, such as neurologic symptoms like dysphonia, diplopia, and muscular weakness. When this patient starts to eat he coughs, which indicates oropharyngeal impairment of the swallowing mechanism rather than an esophageal cause. Patients with oropharyngeal dysphagia typically describe coughing, choking, and nasal regurgitation. Choking occurs owing to failure to clear food from the epiglottis and may lead to aspiration. The initial test of choice for evaluation of oropharyngeal dysphagia is videofluoroscopy (also known as a modified barium swallow) in which the oropharyngeal phase of swallowing is assessed with foods of different consistencies. Oropharyngeal forms of dysphagia are often managed with dietary adjustment and incorporation of swallowing exercises with the assistance of a speech pathologist.

Barium swallow may be useful in the evaluation of esophageal dysphagia following a normal upper endoscopy when a mechanical obstruction is still suspected. For example, upper endoscopy may miss lower esophageal rings or extrinsic compression of the esophagus. A barium swallow will not be as helpful as videofluoroscopy in a patient with oropharyngeal dysphagia.

Esophageal dysphagia tends to occur after the initiation of the swallow. Esophageal manometry is useful to diagnose an esophageal motility disorder such as achalasia. However, it is not the best test in a patient with symptoms of oropharyngeal dysphagia.

Esophageal dysphagia often has an intraluminal cause, such as strictures, Schatzki rings, or masses. The diagnostic test of choice for esophageal dysphagia is upper endoscopy, which can be both diagnostic (allowing biopsy and visualization of the mucosa) and therapeutic (allowing dilation to be performed if indicated).